From Hamas in the Gaza Strip to radical armed movements in Syria, Qatar’s status as a prime sponsor of violent Islamists, including groups linked to al-Qaeda, is clear to diplomats and experts.

Qatar’s promotion of extremism has so infuriated its neighbours that Saudi Arabia, Bahrain and the United Arab Emirates all chose to withdraw their ambassadors from the country in March.

Take Syria, where Qatar has been sponsoring the rebellion against Bashar al-Assad’s regime. In itself, that policy places Qatar alongside the leading Western powers and much of the Arab world.

But Qatar has deliberately channelled guns and cash towards Islamist rebels, notably a group styling itself Ahrar al-Sham, or “Free Men of Syria”. Only last week, Khalid al-Attiyah, the Qatari foreign minister, praised this movement as “purely” Syrian.